Answer: The mulch should be about two inches thick, and should cover any ground where you do not want weeds. Most gardeners will leave it to the side of where seeds are planted so the seedlings can emerge, then thin the seedlings as needed and pull the mulch in between them.
Mulch is an excellent way to reduce weeds, maintain soil moisture and improve the soil as it breaks down over time. You can use partly finished compost, rotted leaves, straw, shredded bark, or any other organic material as mulch. There is one caution in using pine needles as mulch in the vegetable garden, and that is that the pine needles are fairly acidic and can lower the soil pH as they decompose. If your soil is already somewhat acid, this could make it too acid for most vegetables to grow their best. You might want to run some basic soil tests and check it. Your county extension (563-9388) can help you with the tests and interpreting the results.
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